RU2749775C1 - Agricultural harvesting machine with floating system on hydraulic cylinders with electronic control (options) - Google Patents

Abstract

FIELD: agriculture.

SUBSTANCE: group of inventions relates to agriculture. A crop harvesting machine consists of a carrier vehicle, a frame having at least first and second frame portions, each of which has a crop processing component including a crop interaction system and at least one ground interaction component for providing supporting efforts from the ground. The first and second sections of the frame are pivotally connected for pivotal movement relative to each other up and down. To support the first frame portion relative to the vehicle, the first support device is provided comprising at least one first hydraulic floating cylinder and a first hydraulic system. To support the second frame section relative to the first frame section, the second supporting device is provided comprising at least one second hydraulic floating cylinder and a second hydraulic system. To control the first and second hydraulic systems, at least one communication sensor and an electronic control system are provided. A crop harvesting machine includes a carrier vehicle, a frame having at least the first and second frame portions, each of which has a crop processing component including a crop interaction system and at least one ground interaction component for providing supporting efforts from the ground. The first and second frame portions are pivotally connected to pivotally move the second frame portion up and down relative to the first frame portion. To support the first frame portion relative to the vehicle, the first support device is provided having at least one first hydraulic floating cylinder and the first hydraulic system. To support the second frame section relative to the first frame section, the second supporting device is provided including at least one second hydraulic floating cylinder and the second hydraulic system. The first and second lift pressure systems include a common accumulator. An electronic control system is provided to generate a control signal for changing the pressure of at least the first hydraulic system.

EFFECT: proposed is reduced static friction effect to reduce the resistance to cylinder movement during floating movement and a dynamic control system that changes the forces applied by the cylinder in response to the movement of the header relative to the tractor.

28 cl, 10 dwg

Description

The present invention relates to an electronically controlled hydraulic cylinder floating crop harvesting machine for a header mounted on a carrier tractor. In particular, the device firstly provides a structure in which the static friction effect generated by the cylinder seals is significantly reduced to reduce the resistance to movement of the cylinder during floating movement. Second, the device provides a dynamic control system that changes the forces applied by the cylinder in response to the movement of the header relative to the tractor. The present invention can be used in many different interoperable systems such as hay tools, rakes, pick-ups, etc., but is particularly applicable to windrowers or windrowers in which the header is supported by the swather tractor, and to harvesters in which the header is supported by an adapter. harvester connected to the feeder chamber. When used to cut crops during harvest, the header can use a variety of cutting systems, including cutters, rotary mowers, or similar cutting devices.

BACKGROUND TO THE CREATION OF THE INVENTION

Most windrowers on the market have a hydraulic floating header system. Floating systems of this type suspend the header from the windrower so that a small portion of the header weight is supported by the ground. The advantages of this type of hydraulic floating system include the ability to easily adapt to a wide range of weights / header types, the ability to fully adjust the floating system from the cab, few moving parts, compactness, built-in damping effects and a good market reputation.

However, due to internal friction on floating cylinder seals, these systems generally have poor ground bendability unless the weight supported by the ground is significant, in the order of 15% of the header weight. At this level of ground pressure (header weight supported by the ground), wear on the ground-interacting components is significant. Also, when hitting an obstacle, higher ground pressure is undesirable.

In traditional hydraulic floating systems, each of the header floating cylinders is connected to a corresponding accumulator, pressure transducer and pressure control valve. The pressure control valves are in turn connected to a hydraulic pressure source such as a load sensing pump. The controller takes input from the pressure sensors and adjusts the pressure control valves to maintain a known pressure in the accumulator / cylinder circuit. The accumulator / cylinder system acts like a spring, so when the header hits an obstacle and must bypass the obstacle, the accumulator will pressurize and flow into the cylinder to aid movement of the header. When the header should be lowered into a ditch or depression, the floating cylinder feeds oil back into the battery.

MacDon has traditionally used a coil-type spring flotation system that does not have these frictional constraints and usually has better ground bendability. A typical MacDon spring float system can achieve ground pressure on the order of 10% of the header weight while maintaining acceptable ground bend. Spring-loaded floating systems are currently used on MacDon windrowers and harvester adapters.

Floating header systems typically use a fluid circuit that includes an accumulator, hydraulic cylinders, and control valves to provide float functionality. Vehicles may have one hydraulic cylinder or one on each side of the header for lifting and float functions, or they may have separate hydraulic cylinders for lifting and float functions with the ability to independently adjust float force for each side of the header. Typically, the operator selects the desired float setting by operating the rocker switches; wherein one position of the switch reduces the force when the header contacts the ground, and the other position increases the force when the header contacts the ground. Once a float mode setting is selected, the control valves will return to this float setpoint each time a float mode is selected, regardless of subsequent header raise and lower operations.

One aspect of the float setting selected by the operator is that it determines how quickly the header returns, in controlled acceleration or controlled “fall”, to the ground contact position after lifting in response to contact with a raised terrain. If the header falls too slowly, the field areas cannot be worked at the desired height. However, if the header falls too quickly, the header may hit the ground or roll on the ground, resulting in unwanted harsh or annoying ride characteristics. Also, under certain conditions, such as rough terrain, the header can hit the ground hard enough to damage the header and / or crop. Typically, the float setting by the operator will depend at least in part on the speed of the vehicle over ground. Generally, when traveling in a rugged field at a relatively low speed, rounding can be achieved with less header acceleration than higher speed. Thus, to travel at lower speeds, the operator is more likely to use a float mode setting that allows the header to descend more slowly than selected for a higher speed.

SUMMARY OF THE INVENTION

In accordance with the first definition of the invention, there is provided a machine for harvesting agricultural crops, comprising:

a carrier vehicle for moving on the ground in a forward moving direction;

a frame having at least a first frame portion and a second frame portion;

wherein each of the first and second portions of the frame has a crop processing component including a crop interaction system and at least one ground interaction component for providing ground support force;

wherein the first frame portion is pivotally connected to the second frame portion about an axis generally parallel to the forward direction for pivotally moving the second frame portion up and down relative to the first frame portion;

a first support device for supporting the first frame portion relative to the vehicle such that a portion of the support force for balancing the weight of the crop treating component is provided by the lifting force from the support device and the remainder is provided by the ground engaging component by ground pressure;

wherein the first support device is configured to support the crop processing component for floating movement of the first portion of the frame relative to the vehicle up and down, the first support device comprising at least one first hydraulic floating cylinder and a first hydraulic system containing a pressurized hydraulic fluid;

a second supporting device for supporting the second frame portion relative to the first frame portion such that a portion of the supporting force for balancing the weight of the crop cultivating component in the second frame portion is provided by the lifting force from the first frame portion, and the remainder is provided by the ground engaging component of the second frame portion by ground pressure;

wherein the second support device is configured to support the crop processing component for floating movement of the second frame portion relative to the first frame portion up and down, the second support device comprising at least one second hydraulic floating cylinder and a second hydraulic system containing a pressurized hydraulic fluid ;

and an electronic control system for supplying a control signal for changing the pressure of at least the first hydraulic system and receiving a message from at least one communication sensor on said second support device so that said pivotal movement of the second frame section relative to the first frame section changes the pressure in the first hydraulic system.

In accordance with a second definition of the invention, there is provided a machine for harvesting agricultural crops, comprising:

a carrier vehicle for moving on the ground in a forward moving direction;

a frame having at least a first frame portion and a second frame portion;

wherein each of the first and second portions of the frame has a crop processing component including a crop interaction system and at least one ground interaction component for providing ground support force;

wherein the first frame portion is pivotally connected to the second frame portion about an axis generally parallel to the forward direction for pivotally moving the second frame portion up and down relative to the first frame portion;

a first support device for supporting the first frame portion relative to the vehicle such that a portion of the support force for balancing the weight of the crop treating component is provided by the lifting force from the support device and the remainder is provided by the ground engaging component by ground pressure;

wherein the first support device is configured to support the crop processing component for floating movement of the first portion of the frame relative to the vehicle up and down, the first support device comprising at least one first hydraulic floating cylinder and a first hydraulic system containing a pressurized hydraulic fluid;

a second supporting device for supporting the second frame portion relative to the first frame portion such that a portion of the supporting force for balancing the weight of the crop cultivating component in the second frame portion is provided by the lifting force from the first frame portion, and the remainder is provided by the ground engaging component of the second frame portion by ground pressure;

wherein the second support device is configured to support the crop processing component for floating movement of the second frame portion relative to the first frame portion up and down, the second support device comprising at least one second hydraulic floating cylinder and a second hydraulic system containing a pressurized hydraulic fluid ;

wherein the first and second lift pressure systems include a common accumulator such that downward flexion of the second frame portion supplies additional fluid to the cylinder of the first hydraulic system to apply additional lift pressure to the first frame portion, and such that upward flexion of the second frame portion extracts fluid from a cylinder of the first hydraulic system for applying a reduced lift pressure to the first portion of the frame;

and an electronic control system for supplying a control signal for changing the pressure of at least the first hydraulic system.

The device set forth in any of the definitions can be configured such that the electronic control system receives a message from both the first support device and the second support device for changing the pressure of both the first and second hydraulic systems.

The device set forth in any of the definitions can be configured such that the communication sensor comprises a displacement sensor responsive to the movement of the second support system.

The device set forth in any of the definitions can be configured such that the first and second hydraulic floating cylinders cooperate with corresponding first and second valve devices configured to change the pressure in the chamber of the corresponding cylinder to provide the required variable lifting force.

The device set forth in any of the definitions can be configured such that the valve device has the characteristic that the valve device acts to maintain the pressure of the hydraulic fluid in the chamber at a constant value, this value depending on the control signal applied to the valve device during changes in the volume of the chamber caused by the movement of the piston.

The device set forth in any of the definitions can be configured so that the electronic control system is programmed to perform these temporary changes to respond to a movement signal from a displacement sensor, and not to changes in pressure in the chamber caused by the movement of the piston.

In one preferred arrangement, the first hydraulic system comprises a first lifting pressure system configured to apply pressure to the piston side in said at least one first cylinder in the direction of lifting of the crop treatment component, the pressure determining a lifting force in excess of the required lifting force, and the first a down pressure system for applying down pressure in the downward direction of the crop processing component and applying said pressure to the ground, and the second hydraulic system comprises a second up pressure system configured to apply pressure to the piston side in said at least one second cylinder in the up direction crop-treating component, the pressure determining the lifting force in excess of the required lifting force, and a second down pressure system for applying the down pressure pressure in the direction of lowering the crop processing component and applying said pressure to the ground.

The device set forth in any of the definitions can be configured such that the first and second lift pressure systems include a common accumulator so that downward flexion of the second frame section supplies additional fluid to the cylinder of the first hydraulic system to apply additional lift pressure to the first section. the frame and so that upward flexing of the second frame portion extracts fluid from the cylinder of the first hydraulic system to apply a reduced lift pressure to the first frame portion.

Although the device can be used on many different types of machines, the structure is particularly intended for use when the first frame portion comprises a central portion attached to a vehicle and the second frame portion comprises one of a pair of side portions, and when the vehicle comprises a harvester and the crop processing component includes a cutter bar for stubbing the crop.

In accordance with a further definition of the invention, there is provided a crop harvesting machine comprising:

a carrier vehicle for moving on the ground;

a crop-processing component including a crop-interacting system and at least one land-interacting component for providing a supporting force from the earth;

a supporting device for supporting the cultivating component relative to the vehicle for floating movement of the cultivating component up and down so that part of the supporting force for balancing the weight of the cultivating component is provided by the lifting force from the supporting device, and the remainder is provided by the ground-interacting component behind ground pressure account;

moreover, the supporting device contains:

at least one hydraulic floating cylinder having a piston movable in the cylinder such that movement of the piston relative to the cylinder causes said lifting force to be applied to the crop processing component;

a hydraulic system containing a hydraulic fluid under pressure for applying pressure to the side of the piston in the specified at least one cylinder in the direction of the rise of the crop processing component;

moreover, the hydraulic system during operation is configured to provide a pressure that determines the lifting force in excess of the required lifting force;

and a down pressure system for applying a down pressure to the crop treatment component in the direction of lowering the crop treatment component and applying said pressure to the ground;

in which the down pressure system includes an electronic control system for providing a control signal for changing the down pressure.

Although in some cases the hydraulic system is operative to provide a pressure that determines the lift force in excess of the required lift, the lift may also be less, with the result that some of the header weight will be supported by the ground, provided this weight is less than the final weight. desired ground force.

Typically, a crop harvester is a header that is mounted on a combine harvester, but many other crop harvesters can use the system outlined in this document. The ground engaging system is usually a skid member that moves above the ground to keep the cutterbar as close to the ground as possible, but other devices can be used in which the cutter bar is kept raised.

Preferably, the electronic control system operates on the down pressure system rather than the hydraulic system, so that any changes in pressure in the hydraulic system are caused by movement of the system rather than changes in the control signal. That is, the down pressure system is independent of the hydraulic system so that the hydraulic pressure remains substantially unchanged, although changes may occur due to movement of the cylinder supplying fluid to and from the cylinder. Typically, an accumulator is provided in the hydraulic circuit to receive the fluid flow. That is, the pressure from the specified hydraulic system does not change in response to the specified sensor signal.

In some cases, pressure changes are made using a position sensor signal and a pressure sensor signal, but ONLY to maintain proper pressure in the lower accumulator to compensate for leaks, temperature changes, etc. That is, the system does not make changes in this pressure in order to influence changes in ground pressure based on the movement of the header.

For the operation of the electronic control system, a sensor is preferably provided, configured to supply a sensor signal to the electronic control system in response to movement of the crop processing component while floating up and down movement of the crop processing component, wherein the electronic control system in response to the sensor signal is configured temporarily changing the control signal to temporarily change the contact pressure and in response to said sensor signal is configured to subsequently return to the target pressure value. Preferably, the electronic control system, in response to changes in said sensor signal, is configured to temporarily change the control signal to change the tracking force of the tracking pressure system in response to detected movement of the crop treating component.

Preferably, the electronic control system is configured to vary the pressure such that the lifting force from the support device is reduced to apply an increased force to the ground, both when the crop treatment component floats upward from the intermediate float position, and when the crop treatment component floats downward from the intermediate float position. swimming position.

In addition, preferably, the electronic control system and said sensor, in response to said signal, are configured to generate a value indicative of the acceleration and / or speed of the crop interacting system upon said floating up and down movement of the crop processing component, and change the control signal in response by the value of acceleration and / or speed.

In a preferred arrangement, the down pressure system is configured to vary the pressure in the down pressure hydraulic system, wherein hydraulic fluid from the down pressure hydraulic system is fed into the cylinder from the back of the piston to counter the up pressure from the hydraulic system.

In another alternative, the down pressure system comprises a component separate from the cylinder configured to apply down force to the lift link in the direction of counteracting the piston in the cylinder force generated by pressure from the hydraulic system. This could be another cylinder or a gas cylinder, the separate component being configured to generate said downforce in response to fluid pressure.

In accordance with a further definition of the invention, there is provided a crop harvesting machine comprising:

a carrier vehicle for moving on the ground;

a crop-processing component including a crop-interacting system and at least one land-interacting component for providing a supporting force from the earth;

a supporting device for supporting the crop-treating component such that a portion of the supporting force for balancing the weight of the crop-treating component is provided by the lifting force from the supporting device, and the remainder is provided by the ground engaging component by ground pressure;

moreover, the supporting device is configured to support the crop-treating component for floating movement up and down relative to the intermediate floating position of the crop-treating component;

moreover, the supporting device contains:

at least one hydraulic floating cylinder;

a hydraulic system containing a pressurized hydraulic fluid;

electronic control system for supplying a control signal for changing the pressure;

moreover, the electronic control system is configured to change the pressure so that the lifting force from the support device is reduced both when floating the crop-treating component upward from said intermediate floating position and when floating the crop-treating component downward from said intermediate floating position.

Preferably, in addition, the electronic control system and the sensor, in response to the signal, are configured to generate a value indicative of the acceleration and / or speed of the crop-interacting system upon said floating movement of the crop-treating component up and down, and changing the control signal in response to acceleration and / or speed value.

The intermediate position may be limited to a point or a small area, but in some cases the intermediate position includes an area on either side of the point at which the lift is kept constant.

In some cases, the rate of decrease in lifting force on one side of the intermediate point differs from the rate on the other side. That is, the rate of decrease in lifting force when the crop-treating component is moved upward may be greater than when the crop-treating component is moved downward.

In some cases, the reduction in lifting force is directly or linearly proportional to the distance traveled. However, more sophisticated algorithms can be used to vary the lifting force relative to the distance traveled by the crop interacting component.

In particular, the device disclosed herein can provide a crop harvesting machine comprising:

a carrier vehicle for moving on the ground on which the harvest takes place;

a crop-processing component including a crop-interacting system and at least one land-interacting component for providing a supporting force from the earth;

a supporting device for supporting the harvesting component with respect to the vehicle for floating movement of the harvesting component up and down so that part of the supporting force is provided by the supporting device and part is provided by the ground engaging component;

wherein the supporting device includes at least one hydraulic floating cylinder configured so that the supply of hydraulic fluid under hydraulic pressure to said at least one floating cylinder causes a lifting force to be applied to the crop harvesting component by moving said at least one a floating cylinder, and this lifting force is proportional to the specified hydraulic pressure;

wherein said at least one floating cylinder comprises cylinder seals along which one component of said at least one floating cylinder slides relative to another component of said at least one floating cylinder;

a hydraulic fluid source for supplying hydraulic fluid to said at least one floating cylinder at a pressure greater than said hydraulic pressure;

a return line for the specified hydraulic fluid;

a valve device for controlling the flow and pressure of said hydraulic fluid from said source to said at least one floating cylinder;

moreover, the valve device is connected to the specified at least one floating cylinder so that the flow of fluid in the specified at least one floating cylinder and out of it is controlled by the valve device at the specified hydraulic pressure controlled by the valve device;

an electronic control system for supplying a control signal to the valve component to change the specified target pressure depending on the value of the signal;

moreover, the specified valve device contains:

the first connection to the specified source;

a second connection with said at least one floating cylinder,

a third connection for discharging said hydraulic fluid into said return line;

and a valve component configured to control the flow of hydraulic fluid from said source to said at least one floating cylinder and flow of hydraulic fluid from said at least one floating cylinder to said return line to maintain said hydraulic pressure in said at least one floating cylinder at a predetermined value set depending on the specified control signal from the specified control system;

and a device for causing a relative reciprocating motion in alternating wave mode between said one component of said at least one floating cylinder and said other component of said at least one floating cylinder.

The objective is that the alternating wave mode preferably has an amplitude sufficient to prevent static frictional interaction of the seals with the component, to maintain movement between the components on said cylinder seals in order to reduce static friction. The amplitude required for this can vary depending on cylinder pressure and header weight and can be easily determined by a person skilled in the art. The seal or seals in question are usually seals on the cylinder wall on the piston head and / or on the cylinder head on the piston rod. In some cases, cylinders can be used without a seal on the stem. Of course, other designs can also be provided. The act of releasing the seal from another component may require actual movement of the seal along the surface, or may only require bending the seal so that its surface is out of contact with a stationary portion of the component surface. In either case, it can be determined that the amount of force required to move the components in response to the control signal can be reduced to about 10% of the normal value when the alternating signal is not applied.

Preferably, the variable wave mode has a frequency in the range of 5 to 15 Hz.

Preferably, the relative reciprocating motion is provided by an alternating waveform signal supplied by said electronic control system to said valve device to vary said target pressure as a function of the signal value. However, movement can be provided by changes in the pressure of the fluid supplied to the cylinder by a component other than the valve. Various sources for pressure changes can be provided, including mechanical components. Also, other components on the header that generate fluid pressure can be used to provide variable fluid pressure.

The mode can usually be sinusoidal, but other shapes can also be used.

In order to prevent tampering with the float cylinder, preferably the variable wave mode has a frequency in the XXX range. If the valve is of a type that uses a spool to switch between inlet and outlet flow, this frequency is significantly different from the typical range of spool travel frequency.

Since the variable wave mode is used in a situation where the header can remain stationary for a period of time, such as during float mode and there is no change in the ground topography, the variable wave mode can stop when the cylinder is used in the raising or lowering state, during the time of which the cylinder is, of course, constantly moving. This eliminates the need for calculations to obtain a waveform based on detection systems when a waveform is not required.

In addition, the device disclosed herein may provide a crop harvesting machine comprising:

a carrier vehicle for moving on the ground;

a crop-interacting component including a crop-cutting system and at least one land-interacting component to provide a supporting force from the ground;

a supporting device for supporting the harvesting component relative to the vehicle for floating movement of the harvesting component up and down so that a predetermined portion of the supporting force is provided by the supporting device and the remainder is provided by the ground engaging component;

wherein the supporting device includes at least one hydraulic floating cylinder configured so that the supply of hydraulic fluid under hydraulic pressure to said at least one floating cylinder causes a lifting force to be applied to the crop harvesting component by moving said at least one a floating cylinder, and this lifting force is proportional to the specified hydraulic pressure;

a hydraulic fluid source for supplying hydraulic fluid to said at least one floating cylinder at a pressure greater than said hydraulic pressure;

a return line for the specified hydraulic fluid;

a valve device for controlling the flow and pressure of said hydraulic fluid from said source to said at least one floating cylinder;

moreover, the valve device is connected to the specified at least one floating cylinder so that the flow of fluid in the specified at least one floating cylinder and out of it is controlled by the valve device at the specified hydraulic pressure controlled by the valve device;

an electronic control system for supplying a control signal to the valve component to change the specified target pressure depending on the value of the signal;

moreover, the specified valve device contains:

the first connection to the specified source;

a second connection with said at least one floating cylinder,

a third connection for discharging said hydraulic fluid into said return line;

and a valve component configured to control the flow of hydraulic fluid from said source to said at least one floating cylinder and flow of hydraulic fluid from said at least one floating cylinder to said return line to maintain said hydraulic pressure in said at least one floating cylinder at a predetermined value set depending on the specified control signal from the specified control system;

a sensor configured to provide a sensor signal to said electronic control system in response to movement of the harvesting component during said floating up and down movement of the harvesting component;

moreover, the specified electronic control system is configured to provide a specified value of the specified control signal to provide the specified lifting force at a specified value to maintain the specified specified part of the specified supporting force;

wherein said electronic control system, in response to said sensor signal, is configured to temporarily change the control signal to temporarily change the lifting force.

Preferably, the electronic control system, after a temporary change in response to said sensor signal, is configured to return to a predetermined value. Thus, preferably, the electronic control system, in response to changes in said sensor signal, is configured to temporarily change the control signal to change the lifting force and therefore change the response of the hydraulic floating cylinder in response to the detected movement of the harvesting component.

For example, the electronic control system, upon detecting the completion of acceleration in said floating upward movement, is configured to change the control signal to reduce the lifting force to damp the upward movement.

Thus, the control system can be used to dynamically increase or decrease lifting force during header lifting due to ground contact or other obstruction to improve response to ground contact forces. In addition, once contact with the ground has been removed, which stops any further acceleration, lift can be significantly reduced so that the weight of the header again acts in a downward direction, thus damping any further floating upward movement. This eliminates or reduces the likelihood of a situation in which the header is raised by force on the ground or interaction with an obstacle and then remains raised for an extended period of time, which prevents crop cutting while the header remains raised.

It should be understood that dynamic control of the lifting forces based on the movement of the header can be used both in float on the ground and when cutting at a given lift height. In the latter scenario, the float motion is usually provided so that the header can “float” over any obstacle, even if the main cutting action is being performed in an elevated position off the ground. Also in some cases, such as in the case of ditches and embankments, the height of the ground can change quite significantly so that the header interacts with the ground, even if it is nominally installed at a height above the ground. Therefore, in all such cases, the dynamic control of the lifting forces increases the available force to raise the header over a change in ground height or over an obstacle. At the same time, the lift motion stops or decreases when overcoming an obstacle to reduce the time the header stays raised above the desired condition.

When the header is at an elevated cutting height, the downward forces can also be dynamically adjusted to most efficiently return the header to the required cutting height. Thus, the downward forces can be increased at the start of the downward travel and can be reduced toward the end of the downward travel to return the header to the desired height more smoothly.

To provide the best damping force, the electronic control system is preferably configured to change the control signal to reduce the lifting force to a value less than the specified predetermined value. Consequently, the header will accelerate downward with the reduced lift force until the header reaches the ground, whereupon downward acceleration will cease and the control will reapply the setpoint.

In a symmetrical manner, preferably the electronic control system, upon detection of acceleration in a floating downward movement, is adapted to change the control signal to reduce the lifting force to facilitate acceleration in said floating downward movement. That is, when the header travels on the ground without the need for floating movement, and when a depression in the ground requires the header to descend to the lower ground level, the lifting force can be rapidly reduced to assist in moving the header downward using the header weight. Also, the electronic control system, upon detecting the completion of the specified acceleration at the specified floating downward movement, that is, when the header interacts with the ground, can be configured to change the control signal to increase the lifting force to damp the downward movement.

Preferably, the sensor comprises a position sensor for generating a position signal indicative of the position of the cylinder during travel, and the electronic control system is configured to calculate the speed and acceleration of the crop harvesting component based on the position signal. However, other sensor devices may be provided, including, for example, a specific acceleration sensing device and a specific relative motion sensing device, all of which are now readily available in an efficient and inexpensive form due to their widespread use in other fields.

Preferably, the electronic control system is configured to achieve a fully adjustable spring rate for the dynamics of the floating system.

Preferably, the electronic control system is configured to achieve fully adjustable damping for the dynamics of the floating system.

In the present invention, the electronic control system may be configured to achieve fully adjustable floating dynamics based on the operational state of the implement, including, but not limited to, implement height, ground speed, and terrain variation (pitch angle, etc.).

In addition, preferably, the electronic control system is configured to provide the operator with a choice of predetermined floating system dynamics that can be adapted to different field conditions and implements.

To take advantage of the advantages of a hydraulic float system, the apparatus described herein provides a system that reduces the effect of friction in the float system to provide superior ground bendability. This system can be applied to windrowers and harvester adapters or any other agricultural implement that is floating on a holder (hay tools, rakes, pick-ups, etc.). The system can be used with a floating header that cuts crops on the ground, as well as a header that cuts crops at a height above ground level. While the system is particularly useful for floating suspension of the main header from the front of the tractor, the same design can also be used for floating suspension of the sides on a flexible draper header of the type described in US Patterson Patent No. 5,005,343 issued April 9. 1991, the disclosure of which is incorporated herein by reference.

The system described herein contains one or more floating cylinders that are used to suspend the header from the holder. Each cylinder (or near it) is provided with an electronically controlled proportional pressure relief / relief (PPRR) valve that regulates the pressure in that cylinder. The valve is controlled by an electronic controller that accepts pressure (or force) and position / velocity / acceleration feedback from the floating system and modifies the cylinder pressure to achieve the desired floating characteristics. Hydraulic pressure and flow is supplied to the valve from a source, which may be an accumulator charged to a level greater than the maximum pressure required by the floating system, a drive circuit that has a minimum pressure greater than the maximum pressure required by the floating system, or some other hydraulic a source. However, the pressure from the valve is supplied to the cylinder directly and immediately without the accumulator in the circuit, which would otherwise weaken the pressure on the cylinder.

That is, while most systems have a battery that is hydraulically and directly connected to the cylinder in float mode, the present device uses an electronically controlled PPRR valve directly between the pressure source and the float cylinder. This allows the system to very accurately and instantaneously adjust the pressure in the floating cylinder so that it can adjust the pressure based on instantaneous changes in the floating system. Battery systems are much less accurate / sensitive as the change in hydraulic pressure on command is divided between cylinder movement and battery charging.

Each floating cylinder has a corresponding position transducer, pressure transducer and pressure reduction / relief valve. The valve is connected to a pressure source. The controller accepts inputs from sensors and independently controls each PPRR valve based on these inputs. The signal from the position sensor can be directly coupled to the cylinder, or it can be linked to some other floating link (s) that indicate the header position. This signal can be used to calculate the header speed and acceleration in the electronic control system, as well as the header position in the float range. PPRR valves directly control cylinders with no accumulator between valve and cylinder. This is the simplest representation of the system.

In another improvement of the invention, an accumulator, a pressure sensor and a control valve are added to improve the response of the floating system. The controller accepts an input from a pressure transducer and operates a valve to maintain a pressure range in the accumulator that is slightly higher (for example, 200-250 psi (1.38-1.72 MPa)) than the maximum pressure required at the transducers pressure. This maximum pressure is dependent on the weight of the header and can be determined by calibrating using traditional methods in which the lift force is gradually increased until the header is slightly lifted off the ground and by adding a setpoint to that defined value or by using stored values based on header ID for each header size and type.

Using this method, the accumulator can provide instantaneous flow to the PRR valves, probably faster than the load sensing pump can respond to the flow demand.

It should be noted that a floating system of this type can also be used to float the sides on a flexible header by using a cylinder to respond to the weight of the side section near the side section pivot and control this cylinder with the proposed system.

In addition to the above, the electronic control algorithms include a method for controlling the output of the PRR proportional valve to control the cylinder pressure to more efficiently track the header around the ground.

Part of the electronic control used involves the oscillating control signal to the PPRR valve, which applies float pressure to the cylinder. This creates an alternating pressure in the cylinder which causes the cylinder to vibrate slightly. Thus, the cylinder is always in motion and this reduces the effect of friction on the cylinder seals. The pressure swing also helps to compensate for the hysteresis or deadband of the proportional pressure reduction / relief valve. A valve of this type includes a spool that oscillates back and forth between the inlet and outlet positions of the fluid to maintain the pressure at a value determined by a signal to the valve solenoid, the position of the spool being controlled by a pilot connection to the output pressure line. Typically, the pilot connection is internal to the valve itself and does not require a duct to the outlet line or controlled cylinder. This type of valve has a dead band between where it releases pressure and where it releases pressure.

An additional feature of the system is that the system provides programmable spring rates or float damping that can be adapted to a variety of float requirements such as cutting height, ground speed, soil conditions, etc. The spring rate can be instantly and continuously adjusted based on transducer input from the floating system, operator, or other systems such as radar, sonar, or laser obstacle and terrain detection.

An additional feature of the system includes the ability to provide variable damping of the floating system also based on floating requirements or situations.

Another feature includes increasing or decreasing the pressure in the floating cylinder based on the float position and direction of travel. For example, this allows the float pressure to be reduced if the header is detected to move downward (for example, when cutting in a ditch) so that the header will bend around the ground when ground level subsides. A similar adjustment can be made to increase or decrease float pressure if the header is detected to move up an embankment.

Another feature includes increasing or decreasing float cylinder pressure based on header speed and / or acceleration.

Other features of the invention provide the following:

a) Floating pressure fluctuation to reduce the effects of proportional PRR valve hysteresis and friction (mechanical) in the system and on the cylinder seals.

b) Detection of change in float position / direction of last travel / speed (this can be done by sensors measuring cylinder length, float position, etc.) and then decreasing / increasing float pressure to lower or raise the header more quickly.

c) Various float settings based on ground conditions, ground speed, crop, cut in / out of the ground.

d) Programmed spring rate.

Feedback from the pressure sensor may not be required as the system can only use the output signal to the PWM valve. For example, the outlet pressure of a valve can technically be related to the electronic input of the valve, so that when a known signal is applied to the valve, it is possible to know what outlet pressure the valve is set to. Typically, however, a pressure transducer may be required due to changes in valve characteristics due to changes in temperature, wear, vibration, etc., which may be too great to be practical.

The signal from the pressure transducer can be used as feedback to confirm that the valve is actually delivering the desired output pressure as set by the control signal. In this way, a device can be provided in which the feedback is used only intermittently to check the output value, so that the signal from the pressure sensor is not directly and repeatedly used by the control system. That is, the outlet pressure can be checked periodically, and if it is found that the measured outlet pressure does not correspond to the expected value set by the control device, a correction factor is used in subsequent calculations of the control system.

Alternatively, the device can operate when the system knows the header position in the float range (from position sensors) and can use this knowledge to vary float pressure to find the optimum value that places the header with minimum force on the ground based on speed and acceleration.

While variable wave motion is preferably provided by a waveform from the control device, an alternative method can also be used that provides a mechanical mixing option, such as a piston / crank device that causes float pressure fluctuations. For example, the system can use the ripple of the knife drive circuit in the cutter bar.

Various methods of providing float pressure can be used, including pressure in the drive circuit, pressure in the drive circuit with accumulator and check valves, load sensing pump with feedback.

Calibration is usually done in the traditional way, in which the system is operated to increase float pressure until the header is slightly raised off the ground, and then the system is used to increase / decrease float pressure to provide optimum ground contact pressure. Of course, other calibration methods can be used, many of which are known to those skilled in the art.

Preferably, with respect to the embodiments or aspects described above, it should be noted that the valve device has the characteristic that the valve device acts to maintain the pressure of the hydraulic fluid in the chamber at a constant value, this value being dependent on a control signal applied to valve device, during changes in the volume of the chamber caused by the movement of the piston.

Preferably, with respect to the embodiments or aspects described above, it should be noted that the electronic control system for performing these timing changes is programmed to respond to a movement signal and not to changes in chamber pressure that are caused by piston movement. Such a system is not practical for the type of valve used, as the valve acts to maintain a constant pressure in the cylinder until a control signal is calculated requiring a change in pressure. Thus, there is no pressure change that can be detected.

Although the valve is thus designed and operated to maintain a constant pressure despite the movement of the piston in the cylinder, changing the volume of the chamber, the system may include a feedback sensor to ensure that the target pressure is maintained without undue deviation. However, the feedback sensor is not used in calculating the required pressure and therefore the required control signal corresponding to this required pressure.

As explained in more detail below, the cylinder chamber into which the valve assembly supplies the controlled pressure may be on the up-side of the piston such that the pressure increases act to increase the lifting force, or more preferably the controlled pressure is supplied by the valve assembly in such a direction that the pressure increases act to reduce the lifting force. It is typically applied from the downward side of the piston to counterbalance the generally constant accumulator lift applied from the upward side of the piston.

Another feature of the invention is that when the electronic control system operates on the down pressure system, it takes into account the pressure changes in the up pressure system caused by the movement of the piston.

In accordance with another aspect of the invention, there is provided a harvester, comprising:

a carrier vehicle for moving on the ground, the vehicle having a feeder chamber for receiving the harvested crop;

a header including a crop cutting system and at least one ground engaging component for providing ground support force;

a supporting device located between the feeder chamber and the header for supporting the header such that a portion of the supporting force for balancing the weight of the crop processing component is provided by the lifting force from the supporting device, and the remainder is provided by the ground engaging component by ground pressure;

moreover, the supporting device is configured to support the crop-treating component for floating movement up and down relative to the intermediate floating position of the crop-treating component;

wherein the supporting device comprises at least one hydraulic floating cylinder, a hydraulic system containing a pressurized hydraulic fluid, and an electronic control system for supplying a control signal for changing the pressure.

BRIEF DESCRIPTION OF DRAWINGS

In the following, embodiments of the invention will be described in conjunction with the accompanying drawings, in which:

FIG. 1 is a side view of a vehicle having a header and a floating header system in accordance with the present invention. In this embodiment, the vehicle is a windrower.

FIG. 1A is a side view of a vehicle having a header and a floating header system in accordance with the present invention. In this embodiment, the vehicle is a harvester.

FIG. 2 is a schematic illustration of a simple control system arrangement in accordance with the present invention for use in the header shown in FIG. one.

FIG. 3 is a schematic illustration of a second control system device in accordance with the present invention for use in the header shown in FIG. 1, which includes an accumulator as part of a fluid source to provide sufficient and immediate fluid flow to satisfy the PPRR valves.

FIG. 4 is a schematic illustration of a third control system arrangement in accordance with the present invention for use in the header shown in FIG. 1 configured to capture the energy of the floating movement of the header.

FIG. 5 is a block diagram showing the operation of the system.

FIG. 6 is a graph showing the operation of the system for varying ground force in response to header movement.

FIG. 7 is a schematic illustration of a system similar to that shown in FIG. 4, in which lifting force in excess of the lifting force required to raise the header is provided by a hydraulic cylinder and is counteracted by a second cylinder or other pressurized device such as a gas cylinder, the pressure of the second cylinder being controlled by valves.

FIG. 8 is a schematic illustration of a system similar to that shown in FIG. 4 and 7, in which lifting force in excess of the lifting force required to raise the header is provided by a hydraulic cylinder and is counteracted by a mechanical spring device, the spring force generated by the spring being controlled by a mechanical system under the control of a controller.

FIG. 9 is a schematic illustration of a first embodiment of a suspension system in accordance with the invention for a machine that includes a central or first portion and a side or second portion that can pivot about the central portion, and the system includes a first cylinder for providing floating movement of the first a section relative to the carrier vehicle and a floating movement of the second section relative to the first section.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1 illustrates the present invention as applied to a self-propelled windrower 100, however, it should be understood that the principles of the present invention are not limited to a self-propelled windrower or any particular type of harvester having a header. The figure illustrates a windrower 100 that includes a tractor 102 and a header 104. The header 104 is pivotally attached to the front end of the frame or chassis 106 of the windrower 100 so that it can move up and down relative to the chassis 106.

Such attachment of the header 104 to the frame 106 is achieved by a pair of lower levers 108 (only the left one is shown, the right is in the same position and in a mirrored configuration on the right side of the vehicle), pivotally connected at one end with the frame 106, and at the other end with header 104, as well as due to the central upper link 110.

Link 110 can take the form of a single or double hydraulic cylinder 112, the extension and retraction of which is adjustable by the operator to remotely control the angle of the cutterbar 114 on the lower front of the header 104.

Also shown is a single lift / float cylinder 116 connecting the lower arm 108 to the frame 106. The cylinder 116 supports each side of the header, i. E. each side of the header is supported by its own lift / float cylinder 116. Only the left lift / float cylinder 116 is also shown. The right lift / float cylinder 118 is designed, constructed, and positioned identically to the left lift / float cylinder 116 and is identically coupled to the header and frame, but is in a mirrored configuration with respect to the left side of the vehicle.

FIG. 1A shows the same construction applied to a harvester where the harvester tractor is referenced 300 and includes a feeder chamber 301 that can be raised and lowered so that the front end moves up and down under the control of the harvester electronics and a height sensor that determines the position of the header 104 relative to the feeder house. A main frame 303 is attached to the feeder house for movement with it. Header frame 304 is supported on frame 303 by floating cylinders 116 as described herein. Thus, the header can float up and down and can be tilted sideways on two cylinders 116, each located on a respective side of the feeder house. For completeness, it should be noted that the header is a draper header with side draper 305 and a feed draper 306 located behind cutter 128 and ground engaging runner 114.

In both embodiments, a position sensor 120 is provided at a suitable location, which may be located directly on the cylinder, or which in FIG. 1 is connected to and between frame 106 and crank arm 122 and is configured to determine the position of the cylinder. This can be done on the cylinder or elsewhere, such as the relative position of the crank 122 relative to the frame 106. The position sensor shown is a potentiometer that provides a signal that changes as the header moves up and down (vertical travel) relative to the frame 106. In this sense, the position sensor is also a height sensor that detects the height of the header in relation to the tractor. The specific location of the position sensor 120 relative to the frame 106 and relative to the crank 122 may vary depending on the available space, the type of transducer desired, and the resolution of the sensor. It should be noted that in this embodiment, the design of the connection between the cylinder 116 and the crank-style lift arms 108 acts such that the lift provided by the lift arms 108 is not directly proportional to the lift from the cylinder due to variations in the gain in force applied. when moving. The relationship between the lift from the cylinder and the actual lift from the levers on the header must be considered when calculating the required lift from the cylinder and therefore the pressure to be applied to the cylinder, as discussed in more detail below.

Thus, the invention provides a crop harvester, typically a crop harvester, comprising a carrier vehicle 102 for moving on the ground being harvested and a crop processing component, typically a header 104, including including a crop engaging system 114 and at least one earth engaging component or skid plate 128 to provide ground support force. The support device 110, 106, 116, and 108 serves to support the crop header relative to the vehicle to float the crop header up and down so that part of the supporting force is provided by the support device and part is provided by the ground engaging component 128.

The support device includes at least one, and usually two, hydraulic floating cylinders 116 and 117, positioned such that the supply of hydraulic fluid under hydraulic pressure to the floating cylinders 116 and 117 provides a lifting force to the header for harvesting agricultural crops by movement floating cylinder, and the lifting force is proportional to the hydraulic pressure supplied to the cylinder.

The floating cylinders include cylinder seals 116A through which the piston component slides relative to the cylindrical floating cylinder component. The cylinder pressure circuit 10 includes a hydraulic fluid source 12 for supplying hydraulic fluid to the floating cylinder at a pressure greater than a desired hydraulic pressure. Source 12 includes a pump 16 and a drain 14 providing a return line for hydraulic fluid.

The circuit includes two separate sections for supplying pressurized fluid to respective cylinders 116 and 117, each of which includes a respective valve device 18, 20 for adjusting the flow and pressure of hydraulic fluid from the source to the respective cylinders.

As explained above, the valves are of the PPRR type, which include a spool 21 that can slide back and forth within the valve to connect inlet and outlet ports 22, 23 to line 24 to a corresponding cylinder. The spool is driven by solenoid 25 to position the spool in the desired position to generate the required pressure depending on the signal to the solenoid provided by the controller 28 on the control line 29. The spool is also controlled by pilot pressure on lines 30 and 31 respectively connected to the valve inlet and outlet. These valves are commercially available from a variety of suppliers and are known as proportional pressure relief / relief valves. They serve to maintain the pressure in the cylinder, when supplied through line 24, at a predetermined value set by a signal on line 29 from the control system, by repeatedly supplying and discharging fluid relative to the cylinder through holes 22 and 23.

The control signal for the valves is generated and controlled by the electronic control system to change the target pressure in the corresponding cylinder, depending on the value of the applied signal.

Thus, the valve assembly includes a first connection 33 to a source 12 and a second return connection 34 together with a cylinder outlet 24.

The valve component controls the flow of hydraulic fluid from the source to the floating cylinder and the flow of hydraulic fluid from the floating cylinder to the return line to maintain the hydraulic pressure in the floating cylinder at a predetermined value based on a control signal from the control system.

The control system 28 includes a sub-component 35 that serves to generate an alternating signal to provide a device for causing a relative reciprocating movement in alternating waves between the piston component of the floating cylinder and the cylindrical component of the floating cylinder to maintain movement between the components on the cylinder seals to reduce effect of static friction.

That is, the relative reciprocating movement is provided by a signal in the alternating wave mode supplied by the electronic control system to the valve device to change the set pressure depending on the value of the signal in the alternating wave mode.

Subcomponent 35 is controlled by the control system 28 so that the alternating wave mode is applied only when the cylinder is in float mode, and not when the cylinder is used in a raising or lowering state.

The loop further includes pressure sensors 40 and 41 that sense the pressure in the fluid lines to the cylinders to provide a signal that is sent to the control system 28. Since the valves are configured to provide an output pressure in response to an applied control signal, a measurement of the output pressure is theoretically unnecessary. However, given the temperature and other changes that may occur, it is advisable to check the outlet pressure to ensure that it does not deviate over time and maintains the desired value as determined by the control signal. The feedback check provided by the pressure transducers can be performed periodically and is not part of the control system's operation to generate output signals.

Position sensors 120 and 121, which determine the position of the cylinders, provide a signal that is fed back to the control system 28. The system can operate using only the input from the position sensors, since the control system 28 can calculate, based on changes in the signal from the position sensors, both the speed and acceleration of the cylinder and therefore the header. A suitable algorithm for performing such calculations is, of course, well known to those skilled in the art. However, in addition to position sensors, or alternatively, the system may include an accelerometer 42 mounted to the header at one or more suitable locations to provide an output signal indicative of relative header movement and header acceleration.

The loop may further include an operator input 45 that allows the operator to enter various parameters as needed to control the control system 28. The control system also includes input lines responsive to various parameters of the operating header, including, for example, a ground speed indicator 46 and a crop status indicator 47. They are shown only schematically as those skilled in the art can determine suitable input parameters. An additional input line may be provided from the prediction system 48, which may use ground and crop height sensors to tentatively determine the expected shearing height. A signal can be used to predict obstacles or desired changes in stub height so that the control system can generate suitable signals to raise or lower cylinders 116, 117 to the desired position.

The electronic control system is designed to provide dynamic control of the lifting force applied by the cylinders to the header. Thus, in response to any header movement detected by position sensors or other accelerometer and relative motion sensors, the control system can vary the pressure applied to the cylinders by the control valves to increase or decrease lift relative to a set float state to alter header movement.

Thus, for example, upon detection of acceleration in floating upward travel, the control system can act to change the control signal to increase the lifting force to facilitate acceleration in floating upward travel.

In addition, upon detecting completion of upward acceleration in the floating upward movement, the electronic control system may act to modify the control signal to reduce the lifting force to damp the upward movement.

These two dynamic actions can be used, for example, when hitting an obstacle or when raising the ground level quickly to quickly accelerate the header up to lift off the ground, and then to stop the upward movement by damping the header to float down as quickly as possible. To move the header down more quickly, the electronic control system can act to change the control signal to reduce the lift to less than the float setpoint.

Symmetrically, when floating downward acceleration is detected, the electronic control can act to change the control signal to reduce the lifting force to promote acceleration in the floating downward motion, and when it detects the end of floating downward acceleration, to change the control signal to increase the lifting force to damp the motion. down.

FIG. 3 shows a device in which an additional accumulator 60 is provided, which has a pressure sensor 61 and a supply valve 62. This accumulator can be used to provide sufficient fluid flow to the inlet of valves 18 and 20 to meet the requirements for rapid fluid flow into the cylinders, if necessary. Thus, if the pressure source 16 that contains the pump has insufficient flow at start-up, the flow can be supplied by the accumulator.

FIG. 4 shows a possible hydraulic circuit for capturing the floating movement of the header, which can also be used.

In this embodiment, the cylinders 116 and 117 are inverted relative to the cylinders shown in FIG. 2 and 3. Also, the pressure supplied to the cylinders from valves 18 and 20 is opposed by the pressure from the source 201 including the accumulator 200 at constant pressure, so that the lifting force is generated by the pressure difference from the valves 18 and 20 relative to the pressure from the source 201 In other words, the lifting movement is provided by pressure from the source 201, and is counteracted by the pressure supplied by the valves 18 and 20 to reduce the lifting force to the value determined by the valves 18, 20 under the control of the control system 28. In this regard, in order to increase the lifting force, the pressure in the cylinders supplied by the valves 18, 20 decreases, and vice versa.

That is, there is an additional accumulator 200, which supplies power for floating motion to the floating cylinders, which is higher than is usually required for floating motion of the header. PPRR valves 18, 20 are operated to add downward force to cylinders 116, 117 to float the header down to the ground. The control system for PPRR valves is similar to the device described above, but using this system, the flow and / or pressure required to control the floating movement is lower.

Also using this system, the system captures energy from the header floating downward into the accumulator 200 using an intermediate check valve 203, which serves as a check valve used when the floating motion is to be stopped. Pressure sensor 202 and control valve 204 are used in conjunction with controller 28 to control pressure in the battery system.

In most cases, each cylinder 116, 117 in this device will have a separate accumulator 200, independent of the accumulator of the other cylinder. Since piston movement in cylinder 116, 117 changes the volume of the under-piston chamber, which is the up-pressure side of the piston, fluid must pass between the lower / lift chamber and the associated accumulator 200, which will change the chamber pressure since the accumulator has a finite volume. Thus, this change in pressure will change the lift pressure and therefore require a change in downward pressure from the upper chamber and valve 18, 20 to maintain the required total lift. This can be compensated for by using the signal from the sensor to calculate the pressure change that occurs, or more preferably, the pressure on each of the two accumulators 200 is sensed by the pressure sensor 202 and transmitted to the control system 28. This allows the required pressure in the upper or lower chamber to be calculated to account for the required change to obtain a new setpoint for the pressure, as well as the required change to account for the change in lift pressure in the lower chamber.

As indicated above, it is kept constant, which can vary with different operating parameters, and the lift force changes are applied by the upper side of the piston valves 18, 20 to apply a pressure change counteracting the constant upward force from the lower side of the piston.

Thus, the floating cylinders can be used in any orientation and are shown inverted in this embodiment. It should be understood that floating cylinders can also be used in a retractable configuration rather than a push-out configuration. In all FIGS. 2, 3 and 4 header weight down. That is, changes in the pressure supplied by the valves can be used in several different orientations to vary the lift generated by the cylinders.

Sensors for collecting information about the dynamic state of the implement may include a linear potentiometer that measures the extension of the hydraulic cylinder, and a pressure transducer that provides feedback on the applied pressure. In other interpretations, the force transmitted to the implement by the hydraulic cylinder can be monitored by a force transducer, or the height of the implement from the ground can be measured either directly or indirectly.

In addition, instead of calculating speed and acceleration based on a position sensor, displacement sensors and accelerometers can be used to provide direct signals proportional to these values.

The device can be used to achieve a fully adjustable spring rate for the floating dynamics of the implement.

The device can be used to achieve fully adjustable damping for the floating dynamics of the implement.

The device can be used to achieve fully adjustable floating system dynamics based on the operating state of the implement, including, without limitation, implement height, ground speed and terrain changes (tilt angle, etc.).

The device can provide the operator with a choice of predefined floating system dynamics that can adapt to different field conditions and implements.

Although existing floating systems can provide acceptable ground forces when the header is stationary, the force applied, in general, regardless of the state of movement of the header, will still dynamically respond based on its weight rather than the floating system's setpoint. For example, the float system can be set to force 500 lb (226.796 kg) to the ground, but additional force input is required to get the header to accelerate when moving up or down. Based on Newton's second law (F = ma), this extra force will create header acceleration that is inversely proportional to header mass. Therefore, while the header may be statically light (i.e. light when stationary), in order for it to actually move up and down around the ground, its dynamics will still be controlled by its weight, and more high ground forces will be required to actually lift the header. The idea behind this device is that the less the static force on the ground is set, the slower the header can be lowered. This is because the maximum input to the floating system to lower the header is equal to the floating weight of the header. Therefore, the lower the floating weight of the header, the less acceleration will be obtained. The friction in the system will also affect how light the float can be. Friction creates an asymmetry between the required ground force when raising and lowering the header. This results in a higher ground force when lifting and slower travel when lowering. This also creates a limitation on how light the static force on the ground can be set, since the floating weight must be greater than the friction in the system in order for the header to actually lower after being lifted.

The floating system in accordance with the present invention allows these limitations to be reduced since the force exerted by the floating system can be adjusted based on the state of movement of the header. Based on the collected sensor feedback, the controller can actually add more force to the system as the header is raised to facilitate faster lifting with less force to the ground. Additionally, when the header begins to lower, the controller can reduce the applied force so that it descends faster. By adjusting the force provided by the floating system based on the state of movement of the header, the dynamics of the header can be changed so that it is no longer controlled by the weight of the header alone. This can allow the heavy header not only to exert an acceptable force on the ground when stationary, but also to raise and lower as if it actually had a lighter weight. It also overcomes the limitation that the minimum downward acceleration is due to the floating header weight, which also provides less stationary ground force of the floating system than can be achieved with a traditional floating system.

It is desirable to provide mechanical improvements, such as reduced system friction, less deadband in the hydraulic valve, and reduced hydraulic restriction of flow to and from the cylinder, as this will reduce the amount of intervention required by the controller to obtain favorable dynamics. Improving the quality of feedback signals to reduce the effects of noise (both mechanical and electrical) provides the controller with more reliable data from which to base control decisions.

The purpose of the floating system is to reduce the force of the header on the ground to reduce wear and improve the ability to bend around the ground. Today, all floating systems are based on static equilibrium of the weapon. In other words, the force is applied in such a way that it lifts some of the header weight so that the force on the ground is reduced. Provided the header does not move up or down throughout the full float range, this system is effective in reducing effort on the ground. For example, if the header weighs 7000 lb (3175.147 kg) and the float is capable of holding 6800 lb (3084.428 kg), then only 200 lb (90.7185 kg) will contact the ground. However, when considering only the static state of the system, two important factors are ignored, namely friction and inertia.

In a frictionless system, the force on the ground is the same whether the header is raised or lowered (provided this is done very slowly). However, by adding friction to the system, the ground force is no longer the same when lifting and lowering. In fact, the difference between the force on the ground when lifting and lowering is equal to twice the friction in the system. As a result of friction, there is minimal ground force that can be achieved. If this minimum threshold is exceeded, the header will no longer lower under its own influence after lifting, as the floating weight of the header is not sufficient to overcome friction. While minimizing system friction can help reduce this effect, it will still be a limitation of the system.

Another major disadvantage of a floating system based on static balance is that the header dynamics will still be controlled by the header weight when the header is in motion. Based on Newton's second law:

Thus, a 7,000 lb (3175.147 kg) header (no friction) with 200 lb (90.7185 kg) static ground force can achieve a maximum downward acceleration of only 0.03 g. Also, 900 lb (408.233 kg) ground force is required to accelerate header travel up to 0.1 g. Although the static force on the ground can be quite small, the less it becomes, the slower the header can lower after being lifted. Also, the slope of the line (and therefore the force on the ground required to obtain a given acceleration) remains related to the weight of the header, and not to the set point of the float system. Because of this limitation, the header will still dynamically respond as if it weighs 7000 lbs (3175.147 kg); and all that a floating system can change is the static force of the system on the ground. Unsurprisingly, when the effect of friction is combined with this limitation, there are limitations on how light an existing floating system can become before its ability to bend around the ground is degraded.

To improve the dynamic response of the floating system, it is necessary not only to change the static force of the floating system on the ground, but also how much force on the ground is required to raise and lower the header. The hydraulic float system described herein does this by injecting dynamic system state feedback into the float control system. Although many different measurements can be used to output information regarding the dynamic state of the system (e.g., force, hydraulic pressure, or other kinetic measurements), as described herein, the extension of the floating cylinder is measured with a potentiometer, and this signal can be numerically differentiated to determine the total kinematic system state.

To alter header dynamics using a floating system, the input force from the floating system cannot be kept constant; instead, it must vary with the dynamic state (speed and acceleration) of the header. The purpose of the control algorithm is not only to reduce the static force on the ground when the header is stationary, but also to reduce the amount of force required to raise the header and lower the header more quickly (as if the header was lighter). This system provides less ground force as well as better ground contouring ability. The dynamically varying force applied by the floating system can reduce the effect of friction in the system.

The target pressure, calculated from the position, speed and acceleration of the cylinder, is generated using a simple PID controller. This PID controller periodically monitors the difference between the target pressure and the measured pressure and then adjusts the output to minimize error. The PID controller can be supplemented with an open loop lookup table. The ability to stably and reliably maintain the cylinder pressure at the target value allows for a quick and stable cylinder response.

To reduce the amount of hysteresis in the system, an admixture is applied to the output signal to the PWM valve. Dithering is the deliberate addition of "noise" to a signal. In this case, sinusoidal mixing waves were used. It should be noted that although the controller output may be sinusoidal, the pressure fluctuation provided is not necessarily perfectly sinusoidal due to the ability of the hydraulics to reproduce the input signal. The dither signal was calculated and simply added to the output of the PID controller to obtain a common output for the valve.

There are three parameters that can be adjusted to change the mixing behavior; namely the amplitude, period and shape (sine, square, triangular, etc.) of the wave. Many different parameters can be used to reduce hysteresis and improve system response.

Relatively efficient mixing can be achieved using a mixing wave period of only 80-100 ms and an amplitude of only 2% of the total duty cycle of an operating PWM valve, although both a longer period and a higher amplitude of the mixing wave may be needed to achieve this result. ...

The mixing wave period appears to be limited at the lower end by the responsiveness of the PRR valve as well as the ability to deliver the flow required to move the cylinder. Above this lower limit, the mixing wave effect is more directly related to the input power of each half-waveform. As a consequence, a shorter dither period requires a higher amplitude waveform, although a longer dither period may use a lower amplitude waveform. Maintaining the blend amount at 7% and changing the blend period at short blend times <150 ms were not particularly effective. Mixing periods of 200-250ms are effective, although if the mixing period is further extended, the header may shake noticeably. This shaking can be reduced by decreasing the amplitude of the waveform so that the power of each half-waveform is reduced. However, it is best to keep the mixing period as short as possible to improve the system response time, so the shortest mixing period that is effective should be selected.

Any required movement will be provided by only half of the mixing waveform and constrained by the other half. It is helpful to interpret the mixing wave as a controller that sequentially checks to see if the header tends to rise and then checks to see if it tends to lower. The amount of mixing half-wave power required to perform these checks will relate to both system friction and hydraulic responsiveness. It is useful to stop mixing while rising or falling, as half of the mixing wave will oppose the intended motion.

The entry of pressure, position, velocity and acceleration into the control structure is calculated as follows. As discussed above, the cylinder is kept in a constant state of movement by the pressure in the cylinder being constantly slightly varied by a sine wave applied to the valve outlet (called mixing). This can make it difficult to determine the pressure and position of the cylinder as it adds a significant amount of noise. As a result, filtering and averaging technologies are used to distinguish the main movement of the system while ignoring the movement due to mixing. These technologies can be more responsive by using mixing wave properties instead of just more aggressive filtering.

Since mixing creates a change in cylinder pressure as well as position, both of these values are averaged over one period of the mixing wave to reduce the effect of this mixing on the calculation. Therefore, to improve the responsiveness of this calculation, a shorter mixing period is desirable.

Since the speed and acceleration readings are based on the calculation of the difference, they are performed differently from the position and pressure readings; and instead of considering only one mixing period, these calculations consider the last two mixing periods. The position (or velocity) is then compared at the equivalent positions of the mixing wave. This provides a computation that is sensitive to changes in position that are smaller in magnitude than the changes produced by the mixing wave. Also, the calculation is averaged over one mixing period. Velocity is calculated by considering how much the position has changed between the compared locations in the form of an interfering wave. In order for the hydraulic floating system to have sufficient ground bending ability, it is desirable that it mimic the response of a spring. To simulate the spring effect, cylinder extension is used to change the pressure in the cylinder. In this case, a simple linear spring rate has been added. The spring rate is entered by creating a linear function that determines the target pressure based on the measured cylinder extension. This leads to an increase in the required input force as the side portion rises. The equation below shows the most recent spring rate used to change header dynamics:

Based on the existing spring system, it is believed that increasing the header weight when lifting is preferred. This has the effect of shifting the header so that it naturally tends to lower. However, provided that target pressure at a given height results in a non-zero force on the ground, the header should always tend to lower. If the terrain causes extended periods during which the header is raised or lowered, those periods of time will be applied with less or greater force to the ground than the set value. Provided the spring rate is not set too aggressive, this is most likely not a problem, but it may be advisable to provide a more uniform header response throughout the range of travel to prevent lifting too lightly and rapidly when it is too heavy and prone to pushing. when it is too light.

In one arrangement, the header set pressure can follow the sliding average of the header position. This is an effective way of realizing spring stiffness without compromising header pressure characteristics for extended periods of time outside of its normal position. Such a device causes the header to initially strive to return to its last position (either by making it heavier when lifting or lightening when lowering), but adapts to the change in position while maintaining it for a period of time.

In addition to altering header dynamics relative to header position by using spring rate, the header potentiometer signal is also used to change target pressure relative to speed and acceleration. As described above, the speed and acceleration rates are calculated to minimize detection of movement due to mixing so as to focus only on the main movement of the header.

The speed indicator refers to the damping of the system. However, since the header already had an overly damped response, this figure is used to reduce system damping by increasing header movement. This metric has some similarities to the pressures that assist lift and lower, except that instead of adding constant pressure to target, the effect changes with header speed. It should be noted that this indicator will tend to destabilize the header. It is useful to construct a non-linear function based on speed that limits lower speeds and amplifies higher speeds. It would probably also be useful to saturate this figure at its maximum value to ensure that this effect does not reduce the required ground force to raise the header to less than zero (which will cause the header to continue accelerating as it travels upward until it reaches fully raised position).

The acceleration rate refers to the inertia of the system. By increasing acceleration, the controller can reduce the actual inertia of the header to help it respond to input forces as if it weighed less. In practice, however, taking the numeric second derivative from the sensor input is substantially noisy, so this is limited in scope. However, it still makes sense to include a metric that links target pressure directly to header acceleration to some extent. Although initially one constant is used, this metric can be divided into two parameters: one to control the influence of positive accelerations and one to control the influence of negative accelerations.

Positive acceleration refers to when the force on the ground increases and the header begins to rise, or when the header hits the ground after falling. In order for the header to be held after landing, positive accelerations were used to reduce the target controller pressure to some extent. This briefly makes the header heavier on contact with the ground, preventing it from bouncing. This also has the effect of making the header somewhat heavier the first time it is lifted. However, since the acceleration of the header hitting the ground is noticeably greater than the input acceleration when lifting the header, the effect is more noticeable in the event of an impact.

Negative acceleration refers to when the header decelerates during a lift and begins to lower. In order to prevent the header from hanging, negative acceleration is also used to reduce the target header pressure, which makes the header temporarily heavier and therefore less likely to hang. If you start to slow down the header lift speed, it will start to get heavier.

Nonlinear equations can be constructed that use the states of position, speed, and acceleration (as well as other variables such as ground speed, cutting height, and so on) to broadly customize the dynamic response of the system.

Fast and accurate conversion of the target pressure of the control structure to the output float force of the system is essential to optimize the system's response. While the PID feedback structure is quite effective in reproducing target pressure, more advanced control technologies can further improve this response. An open loop lookup table and a PID controller down to a correction factor can be used. It is possible to reduce the effect of valve lag by providing short bursts of current output to the solenoid to help it change directions faster.

Reliable and stable measurement of the position, velocity and acceleration of the cylinder is required for operational control of the floating dynamics without adding instability. It is desirable that these calculations provide a clean signal with minimal latency. In the current configuration, all calculations are related to the blending period, regardless of whether blending is actually active. It may be advisable to switch to two different computations, one when mixing is active and one when it is not active. This can help provide better responsiveness in situations where mixing noise should be ignored.

The hydraulic float system described in this document provides a float system that is more responsive and has improved ground contouring ability and less ground force. The system relies on an electronic controller and sensor feedback to decide how much pressure should be applied to the hydraulic floating cylinder. This pressure is then applied using a proportional pressure reduction / relief valve based on an output from the controller. The resulting system provides a highly customizable hydraulic pressure (and therefore force) provided by the floating system. This allows the floating system to adjust the force provided by the floating system to reduce the effects of friction in the system, as well as fundamentally change the dynamics of the header movement.

Returning to FIG. 6, which shows a graph of the system for varying ground force in response to header movement.

As shown, an intermediate region or center zone is provided that acts as a dead zone in which no changes in ground force are applied, as indicated by reference numeral 91, in response to header height changes detected by sensors 120, 121 described above, which determine position of the cylinders. At each end 92, 93 of the center zone, the force on the ground increases from a predetermined value 95, as indicated by reference numerals 95, 96 on a linear scale, in direct proportion to the height of the ground. It should be noted that the force on the ground increases both with an increase in height from the nominal reference height indicated by the reference numeral 0, and with a decrease in height. The rate of increase in force to the ground when raising the header, as indicated by reference numeral 96, is greater than when lowering the header, as shown by reference numeral 95. The rate of increase can be adapted to provide a header travel response that best maintains the header in contact with the ground. The tempos can be linear as shown. Paces can be more complex, involving areas determined by the speed and / or acceleration of the header as it moves up or down. Preferably, the rate of increase in the downward force from the uplift side of the central zone is greater than from the downstream side, since the uplifting action is often due to a collision with an obstacle, so it is more aggressive or intense when moving requiring more responsiveness of the floating system by decreasing the lift.

The center zone or dead zone 91 may be zero, or it may be a point on the centerline 0, or it may be of finite length to allow small changes in elevation before a float change is introduced to reduce the lifting force causing an increase in ground force. The length of the central zone 91, as well as the proportionality factor 95, 96, can be adjusted by the program.

It will be appreciated that the traditional feeder house of a traditional combine harvester system typically includes a centering system in which the feeder house is continuously raised and lowered in an oscillating manner in an attempt to maintain the header height on the feeder house at mid-float height. That is, the center point is constantly changing as the feeder house attempts to maintain the header float height in the middle of the float range. However, the intermediate area of the center zone is usually halfway between the upper and lower float limits. In a typical system, floating movement can be in the order of 6 inches (15.24 cm) in any direction from the center point. A suitable deadband can be 1 to 2 inches (2.54 to 5.08 cm) so that the cutterbar can float up and down that distance without changing the lift.

An increase in the ground force is achieved in the device shown in FIG. 3 by decreasing the pressure in the cylinders acting to raise the header to reduce the lifting force. In the device shown in FIG. 4, the increase in ground force is achieved by increasing the back pressure from the rear of the cylinder relative to the constant lifting force provided by the lift of the cylinder.

As shown in FIG. 7, a system similar to that shown in FIG. 4, in which a lifting force in excess of the force required to raise the header is provided by a hydraulic cylinder 96 and is counteracted by a second cylinder 97, the pressure of the second cylinder 97 acting in a downward direction against the lifting force from cylinder 96 and is controlled by valves 18, 20, as described above, under the control of controller 28.

As shown in FIG. 8, a system similar to that shown in FIG. 4, in which the lifting force in excess of the force required to raise the header is provided by a hydraulic cylinder 96 and is counteracted by a mechanical spring device 98, the spring force generated by the spring 98 being controlled by the mechanical system 981 under the control of the controller 28.

Thus, the system can go through the following stages:

Stage 1: There is no oil in both accumulators 200 and 60.

Step 2: Charge the lower battery to lift the header off the ground by adding oil from the charging circuit. Lower accumulator set pressure is typically 1500-2400 psi (10.34-16.55 MPa) depending on header weight. After that, the pressure in the lower accumulator is maintained at a fixed value.

Step 3: Charge the top 60 battery with oil. Adding oil from an external charging circuit. Pressure is maintained at 1100-2400 psi (7.58-16.55 MPa) using the draper drive circuit and / or charge valves.

Step 4: Determination of the setpoint value for the floating position. Commands the PPR valve to increase pressure until the header is fully lowered. Lower accumulator pressure has increased by pumping oil into lower accumulator 200. When header is lowered to stop, memorize this pressure as float setpoint.

Stage 5: Swimming mode is active. Pressure adjustments using PPR Valves 18, 20 to balance header weight and maintain desired ground force. The required pressure depends on the position in the float range. Top up oil periodically as needed from a pressure source such as a draper drive circuit. Typically ranges from 1,000 to 3,000 psi (6.89-20.68 MPa). The lower system remains closed. Oil is fed into and out of accumulator 200 as the header floats down and up. The pressure varies depending on the swimming position. Gas pressure depending on the accumulator (excluding temperature changes). We can calculate how much pressure should be in the lower accumulator based on the position sensor based on the amount of oil in the accumulator. Therefore, we can monitor the pressure and keep it within the tolerance range to compensate for leaks, temperature changes, etc. This is done only intermittently and only to compensate for leakage, temperature changes, etc.

The Pressure Reducing / Relieving (PRR) valve regulates pressure from 0 to 820 psi (0-5.65 MPa) based on system requirements. The top accumulator 60 is a storage reservoir for an immediate response. It supplies pressure to both the LH system and the RH system. A position sensor detects cylinder extension on each side. The lower accumulator is set to a fixed pressure and maintained relative to the float position. Each side has its own battery.

This arrangement allows the system to apply "spring rate" to the system, which can add pressure to the top of the cylinder, artificially weighting the header as it floats upward.

The system works to determine the position of the cylinder, from which it derives header speed and acceleration. Based on this, the system determines if the header has been lifted by the ground or if this force has dissipated. If the header no longer accelerates upward (that is, it has lost contact with the ground), the system acts to add pressure to the top of the cylinder and force it to drop to the ground.

The system can add "blend" to the top of the cylinder to keep the piston / rod seals in constant motion to reduce the hysteresis effect.

Returning to the structure shown in FIG. 9, it includes all the components detailed above for controlling the lifting forces in the structure. A crop harvesting machine, in this case a header 104 mounted on a harvester 63, is only shown schematically.

The frame in this embodiment has a first or center frame section 64 and a second or side frame section 65 connected to the center section by a hinge 66 so that the side frame can pivot up and down in response to changes in the ground by the outer end 67 side frame moving up and down. That is, the center frame portion is pivotally connected at a hinge 66 to the side frame portion about an axis generally parallel to the vehicle's forward travel direction for up and down pivot movement.

Each of the center and side frame portions has a crop processing component 114 including a crop engaging system comprising a cutter bar and at least one ground engaging component 128 to provide ground support force, as described above. These components are not shown in the schematic illustration in FIG. 9. It should be understood that there is usually also a second side frame portion symmetrical to the first and mounted in a symmetrical manner as described herein.

A first support device 68 is provided to support the central frame portion 64 relative to the vehicle 63. This support device includes a cylinder 69 connected at the top with a harvester frame member provided at the front of the feeder house (not shown) and at the bottom with link 108 that extends forward to lift link 70 below header center section. Side portion 65 is restrained from pivotal movement downward toward the ground by a support 68A including an additional cylinder 71 coupled between a joint 72 at the center portion and a joint 73 at a side portion at the inner end of the side portion to maintain the side portion at a desired angle with respect to pivot 66.

Cylinders 69 and 71 are constructed and operate as shown and described in relation to FIG. four.

That is, the center portion 64 is supported on two cylinders 69 having the same structure and operation as cylinders 116 and 117, one of which is shown by reference numeral 69 in FIG. 9. The side section cylinder 71 has the same structure and operation as one of the side section cylinders 116, 117. As shown in FIG. 9, the center section cylinder 69 operates in cooperation with the side section cylinder 71.

The symmetrically different center section support cylinder works in cooperation with the second side section cylinder, but they are not shown or described since they are symmetrical to components 69 and 71.

The support cylinders 69 and 71 operate such that a portion of the support force for balancing the weight of the crop treatment component is provided by the lifting force from the support device and the remainder is provided by the ground engaging component by ground pressure. It is clearly described above that cylinders 69 and 71 operate in this manner in relation to sections 64 and 65.

Cylinder 69 includes a piston 74 dividing the cylinder into lower and upper chambers 74A, 74B. The cylinder 71 includes a piston 75 dividing the cylinder into separate chambers 75A, 75B.

Thus, the first support device 68 includes a first hydraulic floating cylinder 69 and a first hydraulic system generally indicated by reference numeral 76. System 76 includes a first portion 76A that supplies pressurized hydraulic fluid to chamber 74A and a second portion 76B supplying pressurized hydraulic fluid to chamber 74B.

The second support device 68A includes a second hydraulic floating cylinder 71 and a second hydraulic system, generally indicated by the reference numeral 80. System 80 includes a first portion 76A, which is common to both cylinders 69 and 71, supplying hydraulic fluid under pressure to chamber 75A; and a second portion 80B supplying pressurized hydraulic fluid to chamber 75B.

Section 76A, which is common to chambers 74A and 75A, includes accumulator 761 charged to the required pressure by charging system 770, pressure sensor 762, check valve 763, path 764 to chamber 74A, and path 765 to chamber 75A.

Section 76B for chamber 74B includes accumulator 766, PPRR valve 767, pressure sensor 768, and path 769 to chamber 74B.

Section 80B for chamber 75B includes accumulator 766, PPRR valve 801, pressure sensor 802, check valve 803, and path 804 to chamber 75B.

A common accumulator 761 for chambers 74A and 75A is used to charge these chambers to a lift pressure in excess of the required lift pressure. The accumulator is charged to the set pressure as described above.

PPRR valves 767 and 801 operate as described above for chambers 74B and 75B.

Electronic control system 81 receives input signals from position sensors 82 and 83 that determine the travel positions of cylinders 69 and 71. Control system 81 provides outputs to control PPR valves 767 and 801 and charging system 770.

As described above, cylinders 69 and 71 provide the lift force from pistons 74 and 75, determined by chambers 74A and 75A, which is set to a desired value by the charging system 761 and maintained at a predetermined value and is only adjusted to prevent deflection. Backpressure is provided by PPRR valves 767 and 801 in chambers 74B and 75B under control of control system 81 using the operations and algorithms described above.

Thus, the control system 81 operates to provide a control signal for changing the pressure of at least the first hydraulic system 76 by controlling the valve 767 to change the back pressure in the chamber 74A, for this, the control system 81 receives a message from the position sensor 83 on the second support device 68A, so that the pivoting movement of the side frame portion relative to the center frame portion changes the pressure in the first hydraulic system of the center portion.

Also, as shown, the control system 81 receives a message from both the position sensor 82 on the first support device and from the sensor 83 on the second support device to vary the pressure in both the first and second hydraulic systems on valves 767 and 801.

As described above, the valve 767 has the characteristic that the valve device acts to maintain the pressure of the hydraulic fluid in the chamber 74B at a constant value depending on the control signal from the control system 81. Optionally, symmetrically and at a different pressure, the valve 801 has the characteristic that the valve device acts to maintain the pressure of the hydraulic fluid in the chamber 75B at a constant value depending on the control signal from the control system 81 during changes in the chamber volume caused by the movement of the piston. ...

The first hydraulic system comprises a first lift pressure system 76A configured to apply pressure to the side of the piston 74 in the cylinder 69 in the direction of raising the crop treatment component, the pressure providing a lift force in excess of the required lift force, and a down pressure system 76B for applying the down pressure in the direction of lowering the crop processing component and applying pressure to the ground. The second hydraulic system 80 comprises a second lifting pressure system formed by the common system 76A configured to apply pressure to the side of the piston 75 in the second cylinder 81 in the direction of raising the crop treatment component, and a second down pressure system 80 for applying down pressure in the downward direction of the crop treatment component. crop component and applying pressure to the ground.

The electronic control system works to change the first and second lift pressure systems, but not the first and second lift pressure systems, which remain constant as set by the 770 charging system.

The first and second lift pressure systems formed by the common system 76A include a common accumulator 761 such that downward flexing of the side frame portion supplies additional fluid from chamber 75A to chamber 74A of cylinder 69 to apply additional lift pressure to the center frame section, and so on. that folding the second frame portion upwardly draws fluid from the cylinder of the first hydraulic system to apply less lift pressure to the first frame portion.

As described above and shown in FIG. 6, control system 81 is configured to vary the pressure in chamber 74A of cylinder 69 such that lift is reduced by both floating upward movement of the crop treatment component from the intermediate float position and floating downward motion of the crop treatment component from the intermediate float position.

As described above, the control system 81 is configured to generate a value indicative of the acceleration and / or speed of the crop processing component at said floating up and down movement of the crop processing component and change the control signal in response to the indicated acceleration and / or speed value.

FIG. 9 illustrates one side of the overall system, with the illustrated components duplicated on the other side of the header, except for the top accumulator 766, as the entire machine requires only one such accumulator, and this accumulator has sufficient pressure and flow to power all four PPRR valves.

In this embodiment, a single accumulator 761 is provided that is used to provide pressure to float the entire side of the header and float the side. The cylinders can be sized such that the pressure required for each of these functions (float and flex) can be substantially the same so that the pilot pressures from the two PPRR valves 767 and 801 can be the same.

With this embodiment, when the side portion is floating upwardly, the pressure in the lower accumulator 761 will naturally decrease as oil will flow out of the accumulator to lift the side portion, resulting in a natural decrease in the lifting force of the floating cylinder 69 even before the pressure changes. on the top of the 75B cylinder with a PPRR valve. This is the desired effect, although not necessary, as the system can provide this control entirely with the PPRR valve. That is, in an alternative device (not shown), the accumulator 761 is divided into two separate accumulators with their own predetermined pressures, each of which charges chambers 74A and 75A, respectively, resulting in the effect by which chambers 74A and 75A communicate to automatically transmit lifting forces , is no longer used and is completely replaced by the back pressure control in chambers 74B and 75B.

Shutoff valves 763 and 803 are shown to lock flex and float in a locked position for use when detaching the header from the combine and / or for transport.

Claims (47)

1. A machine for harvesting agricultural crops, containing: a carrier vehicle for moving on the ground in a forward moving direction; a frame having at least a first frame portion and a second frame portion; wherein each of the first and second portions of the frame has a crop processing component including a crop interaction system and at least one ground interaction component for providing ground support force; wherein the first frame portion is pivotally connected to the second frame portion about an axis generally parallel to the forward direction for pivotally moving the second frame portion up and down relative to the first frame portion; a first support device for supporting the first frame portion relative to the vehicle such that a portion of the support force for balancing the weight of the crop treating component is provided by the lifting force from the support device and the remainder is provided by the ground engaging component by ground pressure; wherein the first support device is configured to support the crop processing component for floating movement of the first portion of the frame relative to the vehicle up and down, the first support device comprising at least one first hydraulic floating cylinder and a first hydraulic system containing a pressurized hydraulic fluid; a second supporting device for supporting the second frame portion relative to the first frame portion such that a portion of the supporting force for balancing the weight of the crop cultivating component in the second frame portion is provided by the lifting force from the first frame portion, and the remainder is provided by the ground engaging component of the second frame portion by ground pressure; wherein the second support device is configured to support the crop processing component for floating movement of the second frame section relative to the first frame section up and down, the second support device comprising at least one second hydraulic floating cylinder and a second hydraulic system containing a pressurized hydraulic fluid ; and an electronic control system for supplying a control signal for changing the pressure of at least one of the first and second hydraulic systems and receiving a message from at least one communication sensor responsive to movement of at least one of the first and second supporting devices. 2. The harvesting machine of claim 1, wherein the electronic control system receives a message from at least one communication sensor on said second support device for changing the pressure of the first hydraulic system such that said pivotal movement of the second frame section relative to the first frame section changes the pressure in the first hydraulic system. 3. Harvesting machine according to claim 1 or 2, wherein the electronic control system receives communication from both the first support device and the second support device to vary the pressure of both the first and second hydraulic systems. 4. The harvesting machine of claim 2, wherein said at least one communication sensor comprises a displacement sensor responsive to movement of the second support system. 5. Machine for harvesting agricultural crops according to any one of paragraphs. 1-4, wherein said first and second hydraulic floating cylinders cooperate with respective first and second valve assemblies adapted to vary the pressure in the chamber of the respective cylinder to provide the required variable lifting force. 6. The harvesting machine of claim 5, wherein the valve device has the characteristic that the valve device acts to maintain the pressure of the hydraulic fluid in the chamber at a constant value, which value depends on a control signal applied to the valve. device during changes in the volume of the chamber caused by the movement of the piston. 7. The harvesting machine of claim 6, wherein said electronic control system is programmed to respond to a displacement signal from a displacement transducer, rather than to changes in chamber pressure caused by piston movement, for performing said temporary changes. 8. Machine for harvesting agricultural crops according to any one of paragraphs. 1-7, wherein said first hydraulic system comprises a first lifting pressure system configured to apply pressure to the piston side in said at least one first cylinder in the direction of lifting of the crop processing component, the pressure determining a lifting force in excess of the required lifting force , and a first down pressure system for applying down pressure in the direction of lowering the crop processing component and applying said pressure to the ground, and said second hydraulic system comprises a second boost pressure system configured to apply pressure to the piston side in said at least one second cylinder in the direction of lifting of the crop processing component, the pressure determining the lifting force in excess of the required lifting force, and a second down pressure system for applying the down pressure pressure in the direction of lowering the crop processing component and applying said pressure to the ground. 9. The harvesting machine of claim 8, wherein the electronic control system operates on the first and second down pressure systems rather than the first and second up pressure systems. 10. Harvesting machine according to claim 8 or 9, wherein the electronic control system operates on the first and second down pressure systems and takes into account pressure changes in the up pressure system. 11. Machine for harvesting agricultural crops according to any one of paragraphs. 8-10, in which a sensor is provided, configured to supply a sensor signal to said electronic control system in response to movement of the crop-processing component during said floating movement of the crop-processing component up and down, said electronic control system in response to said signal the sensor is configured to temporarily change the control signal to temporarily change the clamping pressure, and the specified electronic control system in response to the specified sensor signal is configured to subsequently return to the predetermined value of the clamping pressure. 12. Machine for harvesting agricultural crops according to any one of paragraphs. 1-11, in which the first and second lift pressure systems include a common accumulator such that downward flexion of the second frame portion supplies additional fluid to the cylinder of the first hydraulic system to apply additional lift pressure to the first frame portion and so that the upward flexion of the second the frame portion extracts fluid from the cylinder of the first hydraulic system to apply a reduced lift pressure to the first frame portion. 13. Machine for harvesting agricultural crops according to any one of paragraphs. 1-12, in which the electronic control system is configured to change the pressure in the specified first hydraulic floating cylinder so that the lifting force from the support device is reduced both during the floating movement of the crop processing component upward from the intermediate floating position, and during the floating movement of the agricultural processing culture the component down from said intermediate float position. 14. The harvesting machine of claim 13, wherein said electronic control system and said sensor in response to said signal are configured to generate a value indicative of the acceleration and / or speed of the crop processing component at said floating movement of the crop processing component up and down, and changes in the control signal in response to the indicated value of acceleration and / or speed. 15. Machine for harvesting agricultural crops according to any one of paragraphs. 1-14, wherein said first frame portion comprises a center portion attached to a vehicle and the second frame portion comprises one of a pair of side portions. 16. Machine for harvesting agricultural crops according to any one of paragraphs. 1-15, in which the vehicle comprises a harvester and said crop processing component includes a cutter bar for stubbing a crop. 17. The crop harvesting machine of claim 16, wherein the first frame portion comprises a harvester center portion attached to the harvester feeder chamber, said first support system located between the feeder chamber and the central portion. 18. Machine for harvesting agricultural crops, containing: a carrier vehicle for moving on the ground in a forward moving direction; a frame having at least a first frame portion and a second frame portion; wherein each of the first and second portions of the frame has a crop processing component including a crop interaction system and at least one ground interaction component for providing ground support force; wherein the first frame portion is pivotally connected to the second frame portion about an axis generally parallel to the forward direction for pivotally moving the second frame portion up and down relative to the first frame portion; a first support device for supporting the first frame portion relative to the vehicle such that a portion of the support force for balancing the weight of the crop treating component is provided by the lifting force from the support device and the remainder is provided by the ground engaging component by ground pressure; wherein the first support device is configured to support the crop processing component for floating movement of the first portion of the frame relative to the vehicle up and down, the first support device comprising at least one first hydraulic floating cylinder and a first hydraulic system containing a pressurized hydraulic fluid; a second supporting device for supporting the second frame portion relative to the first frame portion such that a portion of the supporting force for balancing the weight of the crop cultivating component in the second frame portion is provided by the lifting force from the first frame portion, and the remainder is provided by the ground engaging component of the second frame portion by ground pressure; wherein the second support device is configured to support the crop processing component for floating movement of the second frame section relative to the first frame section up and down, the second support device comprising at least one second hydraulic floating cylinder and a second hydraulic system containing a pressurized hydraulic fluid ; wherein the first and second lift pressure systems include a common accumulator such that downward flexion of the second frame portion supplies additional fluid to the cylinder of the first hydraulic system to apply additional lift pressure to the first frame portion, and such that upward flexion of the second frame portion retrieves fluid fluid from the cylinder of the first hydraulic system for applying a reduced lift pressure to the first portion of the frame; and an electronic control system for supplying a control signal for changing the pressure of at least the first hydraulic system. 19. The harvesting machine of claim 18, wherein said electronic control system receives a message from at least one communication sensor on said second support device such that said pivotal movement of the second frame section relative to the first frame section changes the pressure in the first hydraulic system. 20. The harvesting machine of claim 19, wherein said at least one communication sensor comprises a displacement sensor responsive to movement of the second support system. 21. Machine for harvesting agricultural crops according to any one of paragraphs. 18-20, wherein said first and second hydraulic floating cylinders cooperate with respective first and second valve assemblies adapted to vary the pressure in the chamber of the respective cylinder to provide the required variable lifting force. 22. The harvesting machine of claim 21, wherein the valve device has the characteristic that the valve device acts to maintain the pressure of the hydraulic fluid in the chamber at a constant value, which value depends on a control signal applied to the valve. device during changes in the volume of the chamber caused by the movement of the piston. 23. The harvesting machine of claim 22, wherein said electronic control system is programmed to respond to a displacement signal from a displacement transducer, rather than to changes in chamber pressure caused by piston movement, for performing said temporary changes. 24. Machine for harvesting agricultural crops according to any one of paragraphs. 18-23, wherein said first hydraulic system comprises a first lifting pressure system configured to apply pressure to the piston side in said at least one first cylinder in the direction of lifting of the crop processing component, the pressure determining a lifting force in excess of the required lifting force , and a first down pressure system for applying a down pressure in the lowering direction of the crop processing component and applying said pressure to the ground; and said second hydraulic system comprises a second lifting pressure system configured to apply pressure to the piston side in said at least one second cylinder in the direction of lifting of the crop processing component, the pressure determining a lifting force exceeding the required lifting force, and a second pressing system pressure to apply down pressure in the direction of lowering of the crop processing component and apply said pressure to the ground. 25. The harvesting machine of claim 24, wherein the electronic control system operates on the first and second down pressure systems rather than the first and second up pressure systems. 26. Harvesting machine according to claim 24 or 25, in which the electronic control system operates on the first and second down pressure systems and takes into account pressure changes in the up pressure system. 27. Machine for harvesting agricultural crops according to any one of paragraphs. 18-26, in which the electronic control system is configured to change the pressure in the specified first hydraulic floating cylinder so that the lifting force from the support device is reduced both during the floating movement of the crop processing component upward from the intermediate floating position, and during the floating movement of the agricultural processing culture the component down from said intermediate float position. 28. The harvesting machine of claim 27, wherein said electronic control system and said sensor in response to said signal are configured to generate a value indicative of the acceleration and / or speed of the crop processing component at said floating movement of the crop processing component up and down, and changes in the control signal in response to the indicated value of acceleration and / or speed.

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